Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description is the only source of behavioral information, but it offers none beyond the basic action. It doesn't disclose that items are removed from inventory, appear in the world, or are potentially lost, which are critical side effects for a drop operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.